1/*
2 * linux/arch/arm/mach-vexpress/mcpm_platsmp.c
3 *
4 * Created by:  Nicolas Pitre, November 2012
5 * Copyright:   (C) 2012-2013  Linaro Limited
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * Code to handle secondary CPU bringup and hotplug for the cluster power API.
12 */
13
14#include <linux/init.h>
15#include <linux/smp.h>
16#include <linux/spinlock.h>
17
18#include <asm/mcpm.h>
19#include <asm/smp.h>
20#include <asm/smp_plat.h>
21
22static void cpu_to_pcpu(unsigned int cpu,
23			unsigned int *pcpu, unsigned int *pcluster)
24{
25	unsigned int mpidr;
26
27	mpidr = cpu_logical_map(cpu);
28	*pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
29	*pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
30}
31
32static int mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle)
33{
34	unsigned int pcpu, pcluster, ret;
35	extern void secondary_startup(void);
36
37	cpu_to_pcpu(cpu, &pcpu, &pcluster);
38
39	pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n",
40		 __func__, cpu, pcpu, pcluster);
41
42	mcpm_set_entry_vector(pcpu, pcluster, NULL);
43	ret = mcpm_cpu_power_up(pcpu, pcluster);
44	if (ret)
45		return ret;
46	mcpm_set_entry_vector(pcpu, pcluster, secondary_startup);
47	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
48	dsb_sev();
49	return 0;
50}
51
52static void mcpm_secondary_init(unsigned int cpu)
53{
54	mcpm_cpu_powered_up();
55}
56
57#ifdef CONFIG_HOTPLUG_CPU
58
59static int mcpm_cpu_kill(unsigned int cpu)
60{
61	unsigned int pcpu, pcluster;
62
63	cpu_to_pcpu(cpu, &pcpu, &pcluster);
64
65	return !mcpm_wait_for_cpu_powerdown(pcpu, pcluster);
66}
67
68static int mcpm_cpu_disable(unsigned int cpu)
69{
70	/*
71	 * We assume all CPUs may be shut down.
72	 * This would be the hook to use for eventual Secure
73	 * OS migration requests as described in the PSCI spec.
74	 */
75	return 0;
76}
77
78static void mcpm_cpu_die(unsigned int cpu)
79{
80	unsigned int mpidr, pcpu, pcluster;
81	mpidr = read_cpuid_mpidr();
82	pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
83	pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
84	mcpm_set_entry_vector(pcpu, pcluster, NULL);
85	mcpm_cpu_power_down();
86}
87
88#endif
89
90static struct smp_operations __initdata mcpm_smp_ops = {
91	.smp_boot_secondary	= mcpm_boot_secondary,
92	.smp_secondary_init	= mcpm_secondary_init,
93#ifdef CONFIG_HOTPLUG_CPU
94	.cpu_kill		= mcpm_cpu_kill,
95	.cpu_disable		= mcpm_cpu_disable,
96	.cpu_die		= mcpm_cpu_die,
97#endif
98};
99
100void __init mcpm_smp_set_ops(void)
101{
102	smp_set_ops(&mcpm_smp_ops);
103}
104